Magnetic Debris and Particle Detector

ABSTRACT

A system, method and apparatus for determining wear on a component of a tool is disclosed. An oscillating member receives a particle freed from the component as a result of the wear on the component. A measuring device measures a change in a parameter of the oscillating member resulting from receiving the particle. A processor determines the wear on the component from the change in the parameter. In one embodiment, the component may include a component of a downhole tool.

BACKGROUND OF THE DISCLOSURE

1. Field of the Disclosure

The present disclosure relates to determining a wear on a component and,in particular, to determining wear from an effect on an oscillatingmember due to particles worn from the component and accumulated at theoscillating member.

2. Description of the Related Art

Many oil-filled systems include moving parts that experience wear. Overthe course of time, particles are worn away from a surface of the movingparts and are carried away via a fluid surrounding the moving part.While the particles may clutter the system if left in the fluid, theamount of particles is related to the amount of wear that has beenexperienced by the moving part. Thus, determining accumulating theparticles and determine their amount may be useful in determining a wearof the system. Understanding the wear of the system enables having asuitable maintenance schedule.

SUMMARY OF THE DISCLOSURE

In one aspect, the present disclosure provides a method of a determiningwear on a component, the method including: receiving a particle freedfrom the component as a result of the wear on the component onto anoscillating member; measuring a change in a parameter of the oscillatingmember resulting from receiving the particle; and determining the wearon the component from the measured change in the parameter.

In another aspect the present disclosure provides an apparatus fordetermining wear on a component, the apparatus including: an oscillatingmember configured to receive a particle freed from the component as aresult of the wear on the component; a measuring device configured tomeasure a change in a parameter of the oscillating member resulting fromreceiving the particle; and a processor configured to determine the wearon the component from the change in the parameter.

In another aspect, the present disclosure provides a drilling systemthat includes: a component of a drill string; an oscillating member inthe fluid passage configured to receive a particle freed from thecomponent as a result of wear on the component; a measuring deviceconfigured to measure a change in a parameter of the oscillating memberindicative of a change in mass resulting from receiving the particle atthe oscillating member; and a processor configured to determine the wearon the component from the change in the parameter.

Examples of certain features of the apparatus and method disclosedherein are summarized rather broadly in order that the detaileddescription thereof that follows may be better understood. There are, ofcourse, additional features of the apparatus and method disclosedhereinafter that will form the subject of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

For detailed understanding of the present disclosure, references shouldbe made to the following detailed description of the exemplaryembodiment, taken in conjunction with the accompanying drawings, inwhich like elements have been given like numerals and wherein:

FIG. 1 shows an exemplary drilling system suitable for employing anexemplary wear measurement device of the present disclosure;

FIG. 2 shows a detailed view of a section of the exemplary drillingsystem;

FIG. 3 shows a detailed view of the exemplary wear measurement device inone embodiment of the present disclosure;

FIG. 4 shows a detailed view of an active end of the exemplary wearmeasurement device of FIG. 3 in an exemplary embodiment;

FIG. 5 shows a detailed view of an active end of the wear measurementdevice of FIG. 3 in an alternate embodiment; and

FIG. 6 shows a lateral vibrational mode produced at an active end of thewear measurement device in the alternate embodiment.

DETAILED DESCRIPTION OF THE DISCLOSURE

FIG. 1 shows an exemplary drilling system 100 suitable for employing anexemplary wear measurement device 128 of the present disclosure. Theexemplary drilling system 100 includes a derrick 102 and hook 104supporting a drill string 110 disposed in a borehole 108 penetratingformation 106. The drill string 110 includes a drill bit 112 at a bottomend. Pumps 114 circulate drilling fluid through a standpipe 116 andflexible hose 118, down through an interior of the hollow drill string110 to exit at the drill bit 112. The drilling fluid is returned to thesurface via an annular space 120 between the drill string 110 and aborehole wall 122. The drill string 110 may include a bottomholeassembly 124 that may include various components 126 such as movingparts or parts that experience wear in the downhole environment of theborehole 108. The drill string 110 may further include the exemplarywear measurement device 128 within a suitable proximity of the exemplarycomponent 126 for measuring a parameter indicative of the wear on thecomponent 126. A processor 130 conveyed downhole by the drill string 110may perform calculations on the parameters obtained at the exemplarywear measurement device 128 to determine wear on the component 126.Alternatively, the processor 130 may be at a surface location and datameasurements may be telemetered uphole for wear calculations. Inalternate embodiments, the component 126 and the wear measurement device128 may be at any location along the drill string 110.

FIG. 2 shows a detailed view 200 of a section of the exemplary drillingsystem 100. The exemplary system 200 includes a housing 202 that housesa component 204 that experience wear during operation of the drillingsystem 100. A fluid 206 in the housing 202 flows in a directionindicated by flow arrow 208 from the component 204 towards an exemplarywear measurement device 210 of the present disclosure. Althoughdiscussed herein with respect to a drilling system, the exemplary weardetection device 210 may be used with other devices, such as a downholesubmersible pump, an oil-filled system, a gearbox, a hydraulic system,etc. As a result of wear on the component 204, various particles may beworn away or freed from a surface of the component. The particles arecarried by the fluid 206. The wear measurement device 210 is downstreamof the component 204 and thus may receive or accumulate the particle. Asdescribed in further detail below, the reception of the particle at thewear measurement device 210 may change a parameter of the wearmeasurement device 210. The change in the parameter may be measured inorder to determine the presence of the particle at the wear measurementdevice 210 and thus the wear on the component 204 from which theparticle is worn. In particular, a plurality of particles may beaccumulated at the wear measurement device 210 over a selected timeinterval. Measurement of the change of the parameter of the wearmeasurement device 210 over the selected time interval may be used todetermine the rate of wear on the component 204.

A control unit 220 may be coupled to the wear measurement device 210.The exemplary control unit 220 may include a processor 222, a memorylocation 224 for storing various data such as measurements andcalculations performed by the processor 222, and a set of programs 226including instructions that may be used by the processor to determine awear on the component 204. The control unit may be further configured toactuate the wear measurement device 210 by directing a current through acoil 212 proximate the wear measurement device 210. In addition, thecontrol unit 220 may operate the coil 212 in one of an actuation modeand a pickup mode. An electrical measurement device 214 may also becoupled to the coil 212 to measure various electrical parameters such ascurrent, voltage, etc. in a pickup mode of the coil. The variouselectrical parameters may be used to determine wear on the componentusing the processor 222 and the various programs 226. Additionally, thewear measurement device 210 may further include an electromagnet 216that may be turned on and/or off in order to provide a magnetic fieldthat disengages the particles from the wear measurement device 210,thereby preparing a clean wear measurement device once a parameter ofthe wear measurement device 210 has been determined.

FIG. 3 shows a detailed view of the exemplary wear measurement device210 in an exemplary embodiment of the present disclosure. The wearmeasurement device 210 includes a fixture element 302 configured tocouple the wear measurement device 210 to the housing (202, FIG. 2). Thefixture element 302 is coupled to one end of a decoupling stem 304. Anopposing end of the decoupling stem 304 is coupled to a base 306. Thebase 306 supports a first tine 308 and a second tine 310. A constrainedend 308 a of the first tine 308 is coupled to the base 306, and aconstrained end 310 a the second tine 310 is coupled to the base 306. Afree end 308 b of the first tine 308 includes a first magnetic field312, and a free end 310 b of the second tine 310 includes a secondmagnetic field 314. In an exemplary embodiment, a first magnet 316 issecured to the free end 308 b of the first tine 308 in order to providethe first magnetic field 312, and a second magnet 318 is secured to thefree end 310 b of the second tine 310 in order to provide the secondmagnetic field 314. The first magnet 316 and the second magnet 318 maybe permanent magnets. The first magnetic field 312 is substantiallyperpendicular to a longitudinal axis 320 of the first time 308. Thesecond magnetic field 314 is substantially perpendicular to alongitudinal axis 322 of the second tine 310. In an exemplaryembodiment, the first magnetic field 312 and the second magnetic field314 have anti-parallel orientations. In one embodiment, the firstmagnetic field 312 may be directed toward the free end 310 b of thesecond tine 310 and the second magnetic field 314 may be directed towardthe free end 308 b of the first tine 308, as shown in FIG. 4. In analternate embodiment, the first magnetic field 312 may be directed awayfrom the second free end 310 b and the second magnetic field 314 may bedirected away from the first free end 308 b. In general, theorientations of the first magnetic field 312 and the second magneticfield 314 are such that an external magnetic field interacts with thefirst magnetic field 312 and the second magnetic field 314 to produceopposing oscillations on the first tine 308 and the second tine 310, asdiscussed below.

FIG. 4 shows a detailed view of an active end 400 of the exemplary wearmeasurement device 210 in an exemplary embodiment. The active end 400includes the free end 308 b of the first tine 308 and the free end 310 bof the second tine 310 as well as one or more coils 402 a and 402 bdisposed at a selected location with respect to the first and secondfree ends 308 b and 310 b so as to have a magnetic interaction with thefirst and second free ends 308 b and 310 b. The exemplary coils 402 aand 402 b are disposed on opposite sides of a plane substantiallydefined by the first tine 308 and the second tine 310. Each of the oneor more coils 402 a and 402 b are oriented so as to induce a magneticfield 404 directed substantially normal to the plane when a current isconducted through the one or more coils 402 a and 402 b. The one or morecoils 402 a and 402 b may be used as both excitation coils and pickupcoils. As an excitation coil, a current is conducted through the one ormore coils 402 a and 402 b in order to induce magnetic field 404. Inparticular, an alternating current in the one or more coils 402 a and402 b induces an oscillating magnetic field 404. As a pickup coil,changes in the magnetic field due to vibration of the first and secondtines 308 and 310 induce a current in the coils 402 a and 402 b whichmay be measured to determine an oscillation parameter such as frequencyof oscillation, phase of the oscillation, damping of the oscillationand/or amplitude of oscillation of the first and second tines 308 and310.

When exposed to the induced magnetic field 404 of the coils 402 a and402 b operating in the excitation mode, the magnetic fields 312 and 314rotate to align with the induced magnetic field 404. Therefore, for theconfiguration shown in FIG. 4, the first magnetic field 312 rotates in acounter-clockwise direction as indicated by rotational arrow 412,thereby causes a counter-clockwise rotation of the free end 308 b of thefirst tine 308. The second magnetic field 314, being anti-parallel tothe first magnetic field 312, rotates in a clockwise direction asindicated by rotational arrow 414, thereby causes a clockwise rotationof the free end 310 b of the second tine 310. When the current in thecoil is reversed, the direction of the induced magnetic field 404 isalso reversed, thereby causing a clockwise rotation of the free end 308b of the first tine 308 and a counter-clockwise rotation of the free end310 b of the second time 310. Therefore, an alternating current in theone or more coils 402 a and 403 b produces torsional oscillations of thefirst and second tines 308 and 310. The oscillations occur at aneigenfrequency that is determined in part by the mass of the first andsecond tines 308 and 310. The eigenfrequency therefore changes when themass of the first and second times 308 and 310 increases due to theaccumulation of particles. The amplitude and frequency of the torsionaloscillations may be controlled by controlling the frequency andamplitude of the current in the one or more coils 402 a and 402 b.

When operated in the pickup mode, the one or more coils 402 a and 402 bmay be used to measure a parameter of the oscillation of the tines 308and 310, such as a frequency, amplitude, phase and/or damping of theoscillations. The oscillation of the first magnetic field 312 and thesecond magnetic field 314 induce a current in the one or more coils 402a and 402 b. An electrical measuring device (214, FIG. 1) is coupled tothe one more coils 402 a and 402 b to measure an electrical property ofthe one or more coils 402 a and 402 b, such as a current in the one ormore coils 402 a and 402 b or a voltage corresponding to the inducedcurrent.

FIG. 5 shows a detailed view of an active end 500 of the wearmeasurement device in an alternate embodiment. Coil 502 is disposed withrespect to the first and second tines so that a current in the coilsinduces a magnetic field 504 that is oriented substantially along alongitudinal axis of the first tine and/or the second tine. The free end308 b of the first tine 308 is shown for illustrative purposes only.Current in coil 502 induces magnetic field 504. Magnetic field 312 isperpendicular to the induced field 504 and attempts to orient itselfalong the induced field 504. This tendency of the magnetic field 312 toalign with the induced field 504 produces a rotation 508 about a torquevector 510 that is orthogonal to both the direction of the induced field504 and the direction of the magnetic field 312.

FIG. 6 shows a lateral mode produced at an active end of the wearmeasurement device in the alternate embodiment. First tine 308 undergoesa rotation as indicated by rotational arrow 508. For second tine 310,the direction of the magnetic field 314 is anti-parallel to thedirection of the magnetic field 312 of the first tine 308. Therefore,the direction of rotation of the second tine 310 is opposite thedirection of rotation of the first tine, as shown by rotational arrow512. Therefore, the first and second tines 308 and 310 undergo a lateraloscillation within the plane of the first and second tines 308 and 310.

Referring back to FIGS. 2 and 3, in operating the wear measurementdevice 210, a particle is received at one of the magnets 316 and 318,thereby altering an oscillation parameter of the first and second tines308 and 310, such as a frequency of oscillation and/or an amplitude ofoscillation. For example, increase the mass while maintaining the sameexcitation decrease the frequency of oscillation of the first and secondtines 308 and 310 as well as decrease the amplitude of oscillation ofthe first and second tines 308 and 310. The alteration in theoscillation parameter at the coil 212 by an electrical measurementdevice 214 which may measure a change in frequency and/or magnitude fromcurrent flowing through the coil 212. The determined change in theoscillation parameter may therefore be used to determine an amount ormass of particles accumulated at the tines 308 and 310 and therefore andamount of mass lost or worn away from the component 204. This determinedlost mass may provide a determination of the wear on the component.Additionally, the change in the oscillation parameter may be measuredover a selected time interval over which a plurality of particles areaccumulated at the magnets 316 and 318 The change in the oscillationparameter over the selected time interval may then determine a rate ofwear of the component 204.

In another aspect of the present disclosure, the wear measurement device210 may be removed from the housing 202 to remove the particlesaccumulated at the magnets from the fluid. Therefore, the wearmeasurement device 210 also may be used to keep the fluid 206 clean fromwear particles and magnetic debris.

While the foregoing disclosure is directed to the preferred embodimentsof the disclosure, various modifications will be apparent to thoseskilled in the art. It is intended that all variations within the scopeand spirit of the appended claims be embraced by the foregoingdisclosure.

What is claimed is:
 1. A method of a determining wear on a component,comprising: receiving a particle freed from the component as a result ofthe wear on the component onto an oscillating member; measuring a changein a parameter of the oscillating member resulting from receiving theparticle; and determining the wear on the component from the measuredchange in the parameter.
 2. The method of claim 1 further comprisingreceiving a plurality of particles over a selected time interval; andmeasuring the change in the parameter over the selected time interval todetermine a rate of wear on the component.
 3. The method of claim 1,wherein the parameter is at least one of: (i) a frequency of oscillationof the oscillating member; (ii) an amplitude of oscillation of theoscillating member; (iii) a phase of the oscillation; and (iv) anoscillation damping.
 4. The method of claim 1, wherein the oscillatingmember performs at least one of: (i) a torsional oscillation; and (ii) alateral oscillation.
 5. The method of claim 1 further comprisingreceiving the particle on a tuning fork comprising a first tine having aconstrained end coupled to a base and a first free end opposed to theconstrained end, the first free end having a magnetic field; and asecond tine having a constrained end coupled to the base and a secondfree end opposed to the constrained end, the second free end having amagnetic field.
 6. The method of claim 1, wherein the oscillating memberis disposed in a fluid transporting the particle freed from thecomponent
 7. The method of claim 1 further comprising observing thechange in the parameter via observing a current induced in a coil by theoscillating member.
 8. An apparatus for determining wear of a component,comprising: an oscillating member configured to receive a particle freedfrom the component as a result of the wear on the component; a measuringdevice configured to measure a change in a parameter of the oscillatingmember resulting from receiving the particle; and a processor configuredto determine the wear of the component from the change in the parameter.9. The apparatus of claim 8, wherein the oscillating member is furtherconfigured to receive a plurality of particles over a selected timeinterval; and wherein the processor is further configured to measure thechange in the parameter over the selected time interval to determine arate of wear of the component.
 10. The apparatus of claim 8, wherein theparameter is at least one of: (i) a frequency of oscillation of theoscillating member; (ii) an amplitude of oscillation of the oscillatingmember; (iii) a phase of the oscillation; and (iv) an oscillationdamping.
 11. The apparatus of claim 8, wherein the oscillation is atleast one of: (i) a torsional oscillation; and (ii) a lateraloscillation.
 12. The apparatus of claim 8, wherein the oscillatingmember further comprises a tuning fork including: a base, a first tinehaving a constrained end coupled to the base and a first free endopposed to the constrained end, the first free end having a permanentmagnet providing a magnetic field, and a second tine having aconstrained end coupled to the base and a second free end opposed to theconstrained end, the second free end having a permanent magnet providinga magnetic field; wherein the particle is received at one of the firstfree end and the second free end.
 13. The apparatus of claim 12, whereinthe magnetic field of the first tine and the magnetic field of thesecond tine are perpendicular to a magnetic field produced by a coil toactuate an oscillation of the first and second tines.
 14. The apparatusof claim 8, wherein the wear measurement device further includes anelectromagnet configured to disengage particles accumulated at theoscillating member.
 15. The apparatus of claim 8, wherein the measuringdevice is further configured to measure a voltage induced in a coil bythe oscillating member to determine the parameter of the oscillatingmember.
 16. A downhole tool, comprising: a component susceptible to wearduring operation of the tool downhole; an oscillating member in a fluidpassage configured to receive a particle freed from the component as aresult of wear on the component; a measuring device configured tomeasure a change in a parameter of the oscillating member indicative ofa change in mass resulting from receiving the particle at theoscillating member; and a processor configured to determine the wear ofthe component from the change in the parameter.
 17. The downhole tool ofclaim 16, wherein the oscillating member is further configured toreceive a plurality of particles over a selected time interval; and theprocessor is further configured to measure the change in the parameterover the selected time interval to determine a rate of wear of thecomponent from the change in the parameter over the selected timeinterval.
 18. The downhole tool of claim 16, wherein the parameter is atleast one of: (i) a frequency of oscillation of the oscillating member;(ii) an amplitude of oscillation of the oscillating member; (iii) aphase of the oscillation; and (iv) an oscillation damping.
 19. Thedownhole tool of claim 16, wherein the oscillating member furthercomprises a tuning fork including: a base; a first tine having aconstrained end coupled to the base and a first free end opposed to theconstrained end, the first free end having a magnetic field; and asecond tine having a constrained end coupled to the stem and a secondfree end opposed to the constrained end, the second free end having amagnetic field; wherein the particle is received at one of the firstfree end and the second free end.
 20. The downhole tool of claim 19further comprising a coil configured to induce a magnetic field in adirection substantially perpendicular to a direction of the first andsecond magnetic fields; and generate a current in response tooscillation of the first and second magnetic fields.